Sand conditioning apparatus



S. B. DAVIES Dec. 5, 1939.

SAND CONDITIONING APPARATUS- Filed Oct. 17, 1938 2 Sheets-Sheet l Dec. 5, 1939. s. B. DAVIES 2,182,234

SAND CONDITI ONING APPARATUS Filed Oct. 17, 1938 2 Sheets-Sheet 2 iiawmx/ Patented Dec. 5, 1939 UNITED STATES PATENT OFFICE SAND CONDITIONING APPARATUS Application October 17, 1938, Serial No. 235,504

Claims.

The present invention relates to sand conditioning apparatus and is a continuation in part of my copending application, Serial No. 117,609, filed December 24, 1936, now Patent No. 2,133,379. 5 An object of the invention is to provide a hopper construction which will eliminate bridging or building up of the sand or other granular material against the side and rear walls of the hopper as it is delivered to the sand conditioning belt.

A further object is the provision of means for adjustably mounting the rear belt roller to automatically take up slack in the belt and permit a floating action of the roller.

A further object is to provide means cooperating with said roller adjusting means, for eifecting point contact between the roller bearing blocks and frame structure and thereby compensate for misalignment and unequal adjustment of the roller.

With the foregoing and other objects in view, the invention will now be more fully described, reference being had to the accompanying drawings, in which:

Figure l is a side elevation partly in section of the sand conditioning apparatus forming the subject matter of the present invention;

Figure 2 is a horizontal section on line 2-2 of Figure 1;

Figure 3 is a vertical section on line 3-3 of Figure 1;

Figure 4 is a fragmentary section showing the tensioning means, and

Figure 5 is a vertical section on line 55 of Figure 1.

Referring to Figure 1 of the drawings, there is disclosed a sand conditioning apparatus of the type shown in Patent No. 2,133,739 and also in Patent 1,736,055, Boyer, November 19, 1929. In this figure the numeral ll] designates a frame for housing a-sand conditioning belt ll supported on rollers l2 journaled in the frame It. This belt is adapted to be rotated at a relatively high speed and to receive used molders sand from the hop- 45 per l3 and discharge it in a stream from the top of the apparatus in condition for immediate use. The hopper I3 is provided with converging side walls I4 and a rear wall I5 against which pieces of scrap material which have been separated from the sand are adapted to accumulate. The rear wall l5 comprises a movable gate which is supported upon a cross shaft l6 pivotally mounted in the side walls 14 of the hopper.

In the above noted and other Royer patents, 55 the rear gate, when maintained in closed position,

' is located at substantially right angles to the sand conditioning belt. While this arrangement is satisfactory for collecting and periodically disposing of scrap material segregated from the used sand, nevertheless it has been found that there is a tendency for the sand to bridge or build up against the rear wall or gate H: as it is delivered to the belt. The present invention is designed to eliminate this objectionable feature, and this is accomplished by mounting the gate l5 on the shaft 15 so that it will incline forwardly relative to the plane of the belt. As shown in Figure 1, this inclination is quite pronounced. It is to be understood, however, that applicant does not limit himself to any specific degree of inclination other than that the angle is sufiicient to prevent building up or bridging of the sand.

In order that the gate may be easily raised to discharge accumulated scrap, there is provided a handle ll, one end of which is secured to the shaft It. In the closed position of the gate [5 the handle extends substantially longitudinally of the frame and is inclined forwardly and downwardly with its free end supported upon a stop element is carried by the frame. This construction spaces the extreme end of the handle H from the frame and facilitates grasping of the handle. When it is desired to open the gate 15, the handle I1 is raised, and this action rotates the shaft l6 and lifts the lower portion of the gate away from the belt ll sufficiently to permit the discharge of the accumulated scrap.

While the mounting of the gate l5, as above described, is in itself effective to -prevent bridging of the granular material, I have also ascertained that the anti-bridging action is rendered still more effective by forming the lower ends of the side walls of the hopper so that they are substantially vertical. In the above noted Boyer Patent 1,736,055, it will be observed that the side walls of the hopper are inclined inwardly at their lower ends. In the patented construction with the gate at right angles to the belt and with the lower ends of the sides of the hopper inclined inwardly, there is formed a pocket which readily allows wet or sticky sand to build up against the gate. I find that by eliminating the inwardly inclined lower side walls of the hopper, that is, by making the lower ends of these walls vertical and parallel, that all of the granular material falls on the belt without its downward progress being impeded. This new construction is clearly shown in Figures 3 and 5 wherein each converging side l4 terminates in a vertically disposed lower end l9 extending down to a point directly above the belt H. With this construction in cooperation with the forward inclination of the gate 15, any bridging of the sand, particularly when it is wet or sticky, is eliminated, and the efilciency of the machine is greatly facilitated.

To prevent sagging of the upper run of the belt ll between the rollers I2, there is provided a plate 20 (see Figure 5) having side flanges 2| which project upwardly and protect the sides of the belt. A plurality of straps 22 are suspended from the frame and directly support the plate 2%.

Referring particularly to Figures 1 to 4, there is disclosed means for automatically taking up any slack in the belt It and for placing the rear roller l2 under constant tension. This struce ture also cooperates with means for permitting floating movement of the roller, regardless of whether the opposite sides of the roller have been unequally adjusted. The roller I2 is provided with stub shafts 23 which are directly supported in bearing blocks 28. Each block is slidably mounted in a longitudinally extending slot 25 formed in one side of the frame H At a point directly in rear of each slot 25, the frame structure is provided with a cup-shaped recess 26 which communicates with the slot 25 through an opening 27. Each bearing block 24 is rigidly connected to one end of a rod 28 which passes through the opening 2? into its respective recess Coil springs as are positioned in the recesses 25 and are adapted to be placed under compression by adjusting nuts 33 on the thread ed ends of the rods 28. With this arrangement it will be apparent that by screwing up on the nuts 35.3, the bearing blocks 24 and rear roller i2 will be moved rearwardly and thus take up any slack in the 'belt ll. Furthermore, any particles of sand or foreign material that are caught between the belt and roller are permitted to ride around the same without causing damage to the belt or pulley, due to the fact that the roller is fioatably carried in the frame by the spring tensioning means.

Under'ordinary circumstances, if unequal tension is placed on the two bearing blocks 24, it would create a jamming action on the bearing blocks in the slots 25 and destroy thefloating action and automatic adjustment of the roller. This objectionable feature is eliminated in the present construction by providing point contact between the bearing blocks and the frame structure. Referring particularly to Figures 1 to 4, it will be observed that each block 24 is provided with upper and lower flanges 3| and 32; Each flange ti and :52 is provided with an inner curved face 33 which contacts with and slides along a flat machine surface at extending longitudinally of its respective slot 25. As shown in Figures 1 and the machine surfaces 34 are formed on the outer faces of upper and lower flanges 35 and respectively, which border on each of the slots 25.

With the present construction, it will be observed that the curved surfaces 33- of the bearing blocks are adapted to be adjusted along the machined surfaces 34 and by reason of the curvature of the faces 33, each flange has a point contact with its respective surface 36. This is true, regardless of whether the tension on the roller is equal or unequal. For instance, if the nut 3E3 on one side of the roller is adjusted to a point where the roller is thrown slightly out of true axial alignment; nevertheless, by reason of the rocking movement of the curved surfaces 33 on the flat surfaces 341, there will still be a point contact between each of these surfaces which will permit a floating action of the roller and eliminate any binding or looking action between these surfaces.

Referring to Figure 1, the apparatus is shown mounted on a pair of rear wheels 3'! and a front swivel 38 which includes a pair of smaller front wheels 39. A handle 4i] of substantially U-shaped design encompasses the wheels 39 and is pivotally connected to opposite sides of shaft 4|. With this construction the apparatus may be easily and quickly moved from place to place, as desired.

Such variations from the construction herein shown and described as are within the skill of a mechanic may, of course, be made without departing from the range of my invention.

I claim:

1. In a sand conditioning apparatus, a supporting frame having a pair of aligned hearing block receiving slots, a sand conditioning belt mounted in said frame, a belt supporting roller, and a pair of bearing blocks adjustably mounted in said slots and directly supporting said roller, each of said blocks being provided with a curved portion having a point contact with an adjacent flat portion of said frame to compensate for unequal adjustment of the bearing blocks. 2. In a sand conditioning apparatus, a supporting frame having a pair of aligned bearing block receiving slots, said frame being provided with a pair of flat surfaces, each extending along one edge of one of the slots, a sand conditioning belt mounted in said frame, a belt supporting roller, and a pair of bearing blocks adjustably mounted in said slots and directly supporting said roller, each of said blocks having a laterally projecting flange, one face of which is curved and engageable with one of said flat surfaces to provide a point contact and compensate for unequal adjustment of the bearing blocks.

3. In a sand conditioning apparatus, a supporting frame having a pair of aligned bearing block receiving slots, said frame having flat surfaces extending along opposite sides of the slots, a sand conditioning belt mounted in said frame, a belt supporting roller, and a pair of bearing blocks adjustably mounted in said slots and directly supporting said roller, each of said blocks having upper and lower flanges, the inner faces of which are curved and engageable with the flat surfaces on the frame to provide point contacts to compensate for unequal adjustment of the bearing blocks.

4. In a sand conditioning apparatus, a supporting frame having a pair of aligned bearing block slots, a sand conditioning belt mounted in said frame, a belt supporting roller, a pair of bearing blocks positioned in said slots, a rod connected to each block and extending lengthwise of its respective slot and passing through an opening in the frame communicating with the slot, a coil spring surrounding said rod exteriorly of the slot and adapted to be compressed to adjustably maintain the roller under tension, and means for providing point contact between certain portions of said blocks and frame to compensate for unequal adjustment of the bearing blocks.

5. In a sand conditioning apparatus, a supporting frame having a pair of aligned bearing block receiving slots, a sand conditioning belt mounted in said frame, a belt supporting roller, and a pair of bearing blocks adjustably mounted in said slots and directly supporting said roller, said blocks and supporting frame having cooperating flat and curved portions providing point contact between each block and'the frame to compensate for unequal adjustment of the bearing blocks and to prevent binding of said blocks relative to the frame.

STANLEY B. DAVIES. 

